Evidence

The program focuses on reducing violent gun crime by disrupting the cycle of gun violence by relying on forensic science and data analysis to identify, investigate, and prosecute individuals who use guns in criminal activity, and the sources of their guns. The program is rated No Effects. The program did not significantly affect homicides or aggravated assaults with a firearm but was shown to significantly reduce violent crime and robbery with a firearm.

This program equips police with on-officer cameras to record their interactions with civilians. The program is rated No Effects. Camera use had no statistically significant effects on officers’ total number of proactive activities, specifically on the number of traffic stops or business checks, nor on arrests, citizen complaints, and use-of-force incidents. Officers with cameras conducted statistically significantly fewer subject stops, and statistically significantly more park and walks.

This program equips police with body cameras to record encounters with civilians. The program is rated No Effects. Camera use had no statistically significant effects on number of arrests, arrests with force, and summonses issued after 1 year. Officers wearing cameras had statistically significant reductions in complaints filed against them and made more stop reports. Camera use resulted in a statistically significantly reduced likelihood of lawful stops and frisks but fewer subjects searched.

This is a collaborative law enforcement effort to collect, manage, and analyze crime gun evidence to identify serial shooters, disrupt criminal activity, and prevent future gun violence. The program is rated Promising. Posttest gun crime cases saw statistically significant increases in the likelihood of arrest, but no statistically significant difference in the likelihood of being charged or convicted, compared with cases in the pretest period.

This program equips police with on-officer cameras to record contacts with civilians. The program is rated Promising. Body-worn camera use resulted in statistically significant decreases in citizen complaints, and there were mixed results regarding camera use on arrest rates. There were no statistically significant differences in citizen resistance. There was a statistically significant increase in use of force, and less proactive, officer-initiated contact.

This program equips police with on-officer cameras to record contacts with civilians during intimate-partner violence incidents. The program is rated Promising. Camera use was statistically significantly more likely to result in arrests, charges filed, cases furthered, and both guilty pleas and verdicts. There was no statistically significant difference in sentence length. However, there was a statistically significantly greater reduction in case processing time in cases not involving a camera.

This is a criminal investigation method used by law enforcement to increase burglary arrest rates using statistically derived profiles of convicted persons. The intervention was implemented in one police department in Florida for use in active burglary investigations. The program was rated Effective. Results showed a statistically significant increase in burglary arrest rates for the police department that implemented the program.

This program aims to improve police officers’ forensic evidence-collection techniques at burglary crime scenes to increase solved burglaries. The program also intends to improve police–victim and police–witness interactions at burglary crime scenes. The program is rated Promising. Results showed a statistically significant increase in solved burglary cases.

This program aims to improve homicide clearance rates by increasing investigative time through the transfer of four crime scene specialists to the homicide unit. The program is rated No Effects. There were no statistically significant differences between treatment and comparison squads in case and victim clearance by arrest. There were also no statistically significant difference between squads in case and victim clearance by quick action and whodunit arrests, or quality of scene reports.

A problem-oriented policing program that aims to eliminate overt drug markets and the problems associated with them through a deterrence-based, pulling-levers framework. The program is rated Effective. The Intervention had a statistically significant impact on reducing violent incidents in the target areas.

This is a comprehensive antiviolence initiative that uses collaborative strategies to alter perceived costs and benefits of gun violence and is intended to reduce illegal gun offending. The program is rated Promising. Treatment areas experienced a statistically significant reduction in homicide and gun-related homicides, but no reduction in gang-related homicides. In addition, offender notification forums were associated with statistically significant reductions in recidivism rates.

This program provides specialized and coordinated services to victims of sexual assault during their first contact with the health care system. The program is rated Promising. Treatment group patients had a statistically significant greater number of referrals to victim services and greater likelihood of consenting to evidence collection, pregnancy tests, and STD treatment, compared with control group patients treated in the standard emergency room.

This is an automated ballistics imaging and analysis system that populates a computerized database of digital ballistic images of bullets and casings from crime guns, to assist forensic experts in making identifications for police investigations and trials. The program is rated Effective. There was a statistically significant 6.23-fold increase in the monthly number of cold hits generated by the Ballistics Unit after implementation of the automated ballistics imaging and analysis program.

This program consists of a specialized police unit, which was designed to prevent recidivism among people convicted of domestic violence offenses and to assist victims of domestic violence through the process of prosecution and recovery. The program is rated Promising. The treatment group assigned to the Domestic Violence Unit had a statistically significant lower likelihood of recidivating, compared with the control group, who were assigned to standard patrol.

This was a special police unit that conducted raids of crack houses to reduce crack-related crime and improve public order in Kansas City, Mo. The program is rated No Effects. There were no statistically significant differences between the experimental and control groups in calls for service (including calls for violent, property, and disorder offenses) and reported offenses (including violent and property offenses).

This was an experiment to evaluate the impact of deoxyribonucleic acid (DNA) evidence collection and testing on the investigation of high-volume property crimes. The program is rated Effective. Across five sites, more suspects were identified, arrested, and prosecuted in the treatment group cases, compared with suspects in the control group cases. These differences were statistically significant.